Lighting and health

Is the level of ultraviolet light emitted by CFLs a cause for concern?

While it is true that some compact fluorescent lamps (CFLs) do emit slightly more ultraviolet (UV) light than incandescent light bulbs, these emissions are not significant if the CFLs are installed more than 25 centimetres away from people, such as in ceiling fittings.

The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) conducted a study into a range of CFLs, incandescent light bulbs and halogen lamps – Ultraviolet Radiation Emissions from Compact Fluorescent Lights.

Of the tested lamps, those with the highest UV levels measured at a distance of 10 centimetres over a period of 8 hours was equivalent to spending approximately 6 minutes in the midday summer sunshine in Brisbane and 7 minutes in Melbourne. The study found that UV emissions from all lamps decreased rapidly with distance.

A report by the European Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) on the health effects of artificial lighting also examined UV exposure. The report noted that in general, annual UV exposure from household CFLs would at most equal a day in the Mediterranean sun each year for a Danish person.

If you are concerned about UV exposure you should minimise the time spent closer than 25 centimetres from CFLs or use ‘double envelope’ or ‘covered’ CFLs – these types of lamps look similar to ‘pearl’ incandescents.

The Australian Government will continue to monitor developments in relation to potential health effects from UV emissions from CFLs.

Are CFLs safe to use for people with light sensitive conditions?

Slightly more UV light may be emitted by some CFLs when compared to an equivalent incandescent lamp. It has been suggested that a small number of people with very severe light sensitive conditions may be adversely affected by the very small amount of UV light emitted from a bare CFL.

Read more about minimising ultra-violet light exposure from artificial lighting for information relating to possible health implications associated with using CFLs on light sensitive individuals, including those living with lupus.

It is important to note that CFLs are not being mandated. More efficient forms of incandescent lighting will continue to be available, such as mains voltage halogen (MVH) lamps. MVHs have a very similar appearance to the traditional incandescent light bulb, can be used in all of the same fittings, and are readily available. The halogen gas they contain allows them to operate at a higher temperature, which results in higher efficiency levels. However, MVHs are not as energy efficient as CFL alternatives.

As the phase-out plan is developed, the Australian Government will continue to consider health issues and examine options to address any significant concerns. This may include providing information about possible impacts and available alternatives.

Do fluorescent lights provide a light free of visible ‘flicker’?

Some concern has been raised regarding the possible health implications associated with fluorescent light ‘flicker’.

Modern fluorescent lights are free of visible flicker. CFLs operate at a frequency of over 20,000 on/off cycles per second and modern linear fluorescent tubes flicker at a rate of more than 5000 times per second (because of their electronic controllers). These rates of flickering are not detectable by the human brain (studies suggest that one per cent of people can detect a flicker rate of up to 60 times per second), and are also well above the range of flicker commonly associated with photosensitive epilepsy at 5-30 times per second. Experts in the field of epilepsy research have stated that CFLs are no more likely to be a risk to epileptics than other light bulbs (Professor Graham Harding, Epilepsy Action UK).

A small number of cases of reactions to linear fluorescent tube flicker have been recorded. These cases these were almost certainly triggered by old technology which operated at a much lower frequency on a copper-iron magnetic controller, rather than an electronic controller which all modern fluorescent lamps use.

If a linear fluorescent tube has a noticeable flicker it is likely to be faulty and should be replaced.

If a CFL has a noticeable flicker it could be the result of a poor quality product or may occur in situations where the lamp has been incorrectly fitted, such as in a dimmer switch, touch lamp or another electronic device.

What are the potential health risks associated with other types of artificial lighting?

A report by the European Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) has examined the health effects of artificial lighting, including UV exposure and the impacts of artificial light to the eyes, skin, circadian rhythms, sleep and moods. A summary of the effects are given below. Note that these conclusions relate to a wide range of lighting types available.

The SCENIHR report examined a ‘worst case’ exposure to ceiling mounted linear fluorescent lamps with no filters for 6 hours per day (at school) or 8 hours per day (work). The report found that annual UV exposure would add the equivalent of 3-5 days holiday in the Mediterranean sun to the average annual UV dose for a Danish person.

Fluorescent lamps typically emit less than half of the UV radiation assumed in the worst case scenario due to the use of filters which block some of the UV light.

Some people with light sensitive conditions may be adversely affected not only by UV radiation but also the visible part of the light spectrum such as. the light that can be seen. For those people, it may be necessary to avoid lamps which have a significant blue light component. The advice available on minimising ultra-violet light exposure from artificial lighting  is also applicable to these circumstances.

Long-term exposure to artificial light during normal lighting conditions is unlikely to cause damage to the eye. However, improper use or installation of lamps or accidental high-intensity artificial light could result in retinal damage. Manufacturer instructions should always be followed.

The risk of damage to the retina due to blue light radiation can be increased by bright cold white light in close proximity to the eyes (e.g.task lighting) or strong directional lighting (e.g. floodlights, scenic lighting). Exposure to this type of lighting should be minimised where possible.

The SCENIHR report also found that there is some evidence suggesting that exposure to extended light at night may be associated with an increased risk of breast cancer and may also cause sleep, gastrointestinal, cardiovascular and mood disorders. It is thought that this is due to a disruption of circadian rhythms. These effects have not been found to correlate with any specific lighting technology, rather just exposure to light itself.

Concerns have been raised that CFLs may have adverse impacts on the health of some people. One such concern is the effects of CFL ‘flicker’ on sufferers of epilepsy, Ménière’s disease and migraines.

CFL ‘flicker’

As part of their normal operation fluorescent lamps flash on and off very rapidly – CFLs ‘flicker’ at a rate of more than 20,000 times per second, modern linear fluorescent tubes at more than 5000 times per second, and older style linear fluorescents at 100 times per second. These rates of flickering are well above the level detectable by the human brain.

Occasionally, fluorescent lamps may develop a fault which may cause them to have a noticeable flicker – these lamps should be replaced.

Photosensitive epilepsy

Photosensitive epilepsy is the name given to epilepsy in which all, or almost all, seizures are provoked by flashing or flickering light, or some shapes or patterns. Both natural and artificial light may trigger seizures. Various types of seizure may be triggered by flickering light. Photosensitive epilepsy is rare and only 5 per cent of epileptics are diagnosed with this form of epilepsy.

Some known triggers for people with photosensitive epilepsy are:

• watching television or playing video games
• having a faulty lamp or television that flickers
• strobe lights
• driving at dawn or dusk with sun shining through a line of trees
• sun flickering on water
• looking out of the window from a fast moving vehicle
• geometric patterns.

More information about photosensitive epilepsy is available from Epilepsy Action Australia.

The frequency of flashing light most likely to trigger seizures varies from person to person. Generally it is between 8-30 Hertz (Hz) or flashes per second. CFLs ‘flicker’ at a rate well above this sensitive range (over 20,000 Hz) and do not pose a hazard to sufferers of photosensitive epilepsy.

Researchers have concluded that CFLs are no more likely to be a greater risk to people with photosensitive epilepsy than other lamps. Further, the Light Sensitivity Report by the Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) revealed that: “while photosensitivity of epileptics is scientifically proven, seizures induced by flicker can be accurately correlated to the frequency only for a small range (3 Hz, 15–18 Hz). Therefore, there is no scientific data that fluorescent lamps, including compact fluorescent lamps (CFLs) induce seizures.”

Epilepsy Action Australia suggests that fluorescent lights should normally not cause a problem for photosensitive epileptics, except when using faulty lamps which may flicker at a lower frequency visible by the human eye.

In addition, much higher risks are connected with television and video games.

Ménière’s disease

Ménière’s disease afflicts about 0.2 per cent of the population. It is a condition where excess fluid in the inner ear upsets the ear’s balance and hearing mechanisms. This produces symptoms such as vertigo (dizziness), tinnitus (ringing in the ears) and hearing loss. The disorder usually affects only one ear and is a common cause of hearing loss.

There is no scientific evidence to suggest CFLs (or any fluorescent lights) can exacerbate or initiate symptoms of Ménière’s disease. There are however, anecdotal reports that sufferers of Ménière’s disease are more sensitive to flashing lights than others (because of their impaired balance systems), and so may be more susceptible to a phenomenon known as flicker vertigo.

Flicker vertigo may arise from flicker rates in the range of 4–30 Hertz or 4–30 times per second. Symptoms range from vague and non-specific feelings of unease through to nausea, dizziness, migraines, unconsciousness, and even photosensitive epileptic seizures. Flicker vertigo can reportedly affect anyone, but some individuals may be more susceptible than others. Triggering events can be as simple as viewing fast moving objects (such as fan blades, helicopter blades or a tree line from a moving car) that intermittently obscure the sun, creating a flickering effect.

CFLs ‘flicker’ at a rate well above that detectable by the human brain and so should not affect Meniere’s sufferers.

Migraines

Migraine is one of the most common diseases of the nervous system. In developed countries migraine affects about 10–15 per cent of people. Migraines can be triggered by many different things, including stress, exercise, certain foods, bright light, flickering light, loud noises, strong smells, lack of sleep or too much sleep. In women, attacks may be triggered by hormonal changes, for example during menstruation.

If light is suspected as the triggering event for migraines, ordinary headaches, or even eyestrain, the primary cause is likely to be glare, highly contrasting, or inappropriate light levels. These problems are a result of poor lighting design rather than a feature of fluorescent lamps and can occur with any lighting technology if used inappropriately. Light fittings that enclose lamps and distribute light evenly without compromising light output and efficiency can help avoid these problems.

The UK migraine action association recommends:

• ensuring that lighting is adequate and well positioned
• fluorescent lighting should be properly maintained to minimise flicker
• fluorescent lamps should be fitted with the correct type of diffuser to imitate natural daylight as much as possible
• avoid reflected glare from shiny/polished surfaces, plain white walls etc, opt for matt finishes and break up surfaces with pictures, posters or plants
• fit adjustable blinds to windows.

While light sources with a detectable flicker can trigger migraines in susceptible individuals, CFLs ‘flicker’ at a rate well above that detectable by the human brain and so should not affect migraine sufferers.

Alternatives for individuals with photosensitive epilepsy, Ménière’s disease or migraines

It is important to note that CFLs are not being mandated. More efficient forms of incandescent lighting will continue to be available, such as mains voltage halogen (MVH) lamps. MVHs have a very similar appearance to the traditional incandescent light bulb, can be used in all of the same fittings, and are readily available. The halogen gas they contain allows them to operate at a higher temperature, which results in higher efficiency levels. However, MVHs are not as energy efficient as CFL alternatives.

When changing from an inefficient incandescent lamp to a more efficient alternative, make sure that you select a product with an equivalent light output (or brightness) to the lights you already have in your home. The light globe conversion table is designed to assist you in your selection of a more energy efficient lighting alternative that best suits your lighting requirements.

As the phase-out of inefficient light bulbs progresses, the Australian Government will continue to consider health issues and examine options to address any significant concerns. This may include providing information about possible impacts on sufferers of photosensitive epilepsy, Ménière’s disease and migraines, and/or information about new and emerging lighting alternatives.

Nearly all light sources emit ultra-violet (UV) radiation. Sitting close to a compact fluorescent lamp (CFL) or halogen lamp, and being able to see the exposed light bulb means that some UV radiation will be received from the bulb. This is depicted in diagrams A and B.

Diagram A – the pendant light fixture shown allows light emitted from the CFL to directly reach people in the room, in this case the person sitting at the table underneath the light.

Diagram B – the floor lamp shown allows light emitted from the CFL to directly reach the person sitting in the armchair next to the lamp.

Most people will not be affected by the minimal amount of UV radiation that is emitted by these light bulbs, however, a person who is sensitive to UV and/or blue light, such as those who suffer from systemic lupus erythematosus, can use one or more of the following lamps or techniques to minimise the UV radiation reaching them.

Systemic Lupus Erythematosus, more commonly known as lupus, in its many forms, is an autoimmune disorder characterised by chronic inflammation of body tissues. People with lupus produce antibodies that target their own healthy tissues and organs. The cause of lupus is not clear but genetics, viruses, UV emissions, and medication all appear to play some role. Lupus is up to eight times more common in women than men. Exacerbations or flare-ups of lupus can be induced by exposure to any form of UV emissions including sunlight.

Filtering methods – enclosed lamp fixtures

The level of UV emissions reaching you can be reduced by filtering the UV from the light reaching you. Perhaps one of the simplest filtering methods available is a common lamp shade – most of which are UV absorbent. As a general rule plastics are more absorbent of UV than glass shades. The shade needs to be one that is shading you from the bulb in all possible positions that you may be in throughout the room so as to limit the possibility of direct UV exposure—that is, you cannot directly see the bare bulb unobstructed from any position in the room.

The best type of fixture is one which completely encloses the lamp within the fixture, for example, an opal sphere or globe fixture. These are depicted below in diagrams C, D and E.

Diagram C – the CFL is completely enclosed within the surface oyster lamp fitting (lamp shade), which filters the light reaching the person at the table below. This type of fitting also reflects light off the ceiling.

Diagram D – the CFL is completely enclosed within the opal sphere lamp shade which filters the light reaching the person at the table below.

Diagram E – the CFL is completely enclosed within the globe lamp fitting on the floor lamp, which filters the light reaching the person in the armchair next to the lamp.

Reflection methods – indirect lighting

Reflecting light from a lamp off an interior surface to light a room will significantly reduce UV levels. This lighting arrangement is commonly achieved through cove or torchiere-style lighting, where the lamp is obscured from the occupants by a pelmet or lamp fixture as shown in diagrams C and F. The light from the fixture reflects off the wall or the ceiling, and in doing so minimises the UV because paint absorbs a significant amount of UV radiation.

Diagram F – the light is emitted up and out of the lamp shades of the floor lamp and wall light fixture to reflect the light from surfaces such as the walls and ceiling.

Distance

UV levels rapidly decrease as you move further away from any light source. By doubling the distance between yourself and the lamp, UV can be reduced by 75 per cent. Simply moving your desk lamp or bedside lamp slightly further away is a very effective method of reducing UV exposure. However, it will depend on your level of sensitivity, and how much UV is emitted from the lamp. It may not be possible to increase the distance between you and your lamp fitting in all situations, particularly if your lamp fitting is fixed to a wall or ceiling. Information about UV emissions and distances from compact fluorescent lamps can be found on the Australian Radiation Protection and Nuclear Safety Agency website.

Double envelope CFLs

Double envelope CFLs have a cover such as a second layer of glass or plastic over the spiral or bent glass tube. The cover makes them look like a traditional pear-shaped light bulb. This second envelope can block most of the UV emitted from the bulb. The amount of UV blocked by the second layer varies between products, however some models have been found to be lower in UV emissions than incandescent lamps of an equivalent visible light output.

Light emitting diodes (LEDs)

A recent report by the European Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) has suggested that LEDs may provide a good alternative option for people with photosensitive skin disorders, as they emit little or no UV radiation.

LEDs are a new technology and it is unknown if they will also affect some people with photosensitive skin disorders. For people whose sensitivity extends into the visible light spectrum, careful selection is needed as many currently available white LEDs have a strong blue light component.

Maximise UV reduction by using multiple methods

Using a combination of the methods described above will reduce the UV levels to their lowest levels using practical and cost effective techniques. Visible light levels and lighting quality within the room does not need to be compromised to reduce UV exposure.